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DELETED! (SEmMINoLr)
Project 8.5 —- Airborne High Resolution Spectral Analysis - R. Zirkind
OBJECTIVE
To determine the spectral characteristics of the radiant power
of a 30 - 40 kiloton burst as a function of wavelength and the fireball color temperature as seen from an airborne station.

These ob-

jectives are to be accomplished by determining the atmospheric attenuation by an independent measurement and correcting the irradiance

received at the instrument station aboard the aircraft.
INSTRUMENTATION
The spectral distribution of the radiant power is obtained from a medium quartz Hilger spectrometer.

The spectrum is sampled in nar-

row bands by photocells in the visible region and PbS cells in the
infra-red.

The electrical signal is then recorded on an Ampex 814

tape recorder, with a resolution time of 150 ~.sec,

The transmission

Measurement is accomplished by beaming a pulsed light signal of known
output and spectral distribution from a fixed point on the ground
towards the aircraft.

The attenuated beam is received by a detector

in the aircraft and recorded on a Heiland recorder.

The detector con-

sists of two filtered photomultiplier tubes sampling two spectral

regions, (1) .3-.55 microns and (2) .6-1.05 microns,

In addition, a

quartz filtered calorimeter, 22 degrees field of view, is utilized to
Measure the approximate radiant exposure received at the spectrometer.

RESULTS
The P2V aircraft aborted at H-30 minutes due to an engine failure.
Aircraft and crew returned safely.

On SEMINOLE plus 2 days the engine

was replaced and aircraft placed in operational readiness condition
for the next shot.

COPIEDpoe

~ 2 =

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